Steam pumping-engine



D. A. DECROW.

STEAM PUMPING ENGINE.

APPLlCATION FILED APR. 3. l9l8.

Patented June 7, 1921.

3 SHEETS-SHEET I.

D. A. DECROW.

STEAM PUMPING ENGINE.

APPHCATION FILED APR. 3. I918.

Patented June 7, 1921.

3 SHEETS-SHEET 2.

D. A. DECROW.

STEAM PUMPING ENGINE.

APPHCATION FILED APR. 3, 1918.

1,380,365. Patented June 7, 1921.

3 SHEETSSHEET PATENT DAVID A. DECROW, 0F BUFFALO, NEW YORK, ASSIGNOR '10 WORTHINGTON PUMP ANT) MACHINERY CORPORATION, A CORPORATION OF VIRGIN IA.

STEAM PUMPING-ENGINE.

A plication filed April 3,

To all whom it may concern:

Be it known that I, DAVID A. Dnonow, a citizen of the United "States, residin at Buffalo, county of Erie, and State of New York, have invented certain new and useful Improvements in Steam Pumping-Engines, fully described and represented in the fol-' lowing specification and the accompanying drawings, forming a part of the same.

This invention relates to steam englnes and particularly to a combined engine and pump, the especial object of the invention being to provide a steam operated pumping engine capable of operating efiiciently and economically at very high s eeds.

A further object of the lnvention is to provide a steam engine particularly adapted for high speed pumping that is simple and convenient in He construction and includes valve gear that is readily assembled and taken down.

The following specification describes and the accompanying drawings illustrate an engine constructed in accordance with the invention, it being understood that changes may be made in the form, construction and arrangement of the arts without departing from the invention, the form herein disclosed being a referred embodiment thereof.

In the rawingsz- Figure 1 is a view in side elevation of a combined engine and pump constructed in accordance with the invention.

Fig. 2 is a top plan view of a portion of the same.

-llig. 3 is an enlarged cross sectional view, with parts in plan.

Fig. 4 is an enlarged cross sectional view showing a portion of Fig. 3 in a ditierent section, and

Fig. 5 is a vertical sectional view with parts in elevation.

Referring to the drawings, the engine a double acting unitlow engine having the piston 21 and cylinder 22. Steam ad mitted as, hereinafter described alternately at each. end of the cylinder through steam chests 37 having supply pipes 38, 39, and em hausts through central ports 23 into exhaust belt 24:. Piston 21 is mounted one piston rod 25 having suitable connection with the engine crank (not shown) which drives the engine shaft 26 and 27 is the plunger rod of the pump. The ump is tied to the sin gins by rods 28 an is shown double Specification of Letters Patent.

Patented J une '7, 1921.

1918. Serial No. 226,509.

acting center packed pump, having pulsation chambers 29, suction chamber 30,- suction pipe 31, discharge and air chambers 32.

and discharge livery pipe 34:.

The invention includes a construction such that the valve gear for controlling the admission of steam to the cylinder is readily removable entirely and is also readily taken down for removal of various parts. Tothis end, the valve gear at each end of the cylinder is so located that the axial line thereof is offset from the plunger rod 27 or piston rod 25 so that the valve stem may be withdrawn past these and bodily removed. The valve chests and valve gear at opposite ends of the cylinder are the same, so that description of one will suifice. Referring more particularly to Figs. 3 and 5, the cylinder is connected with the valve chest by a port 43 controlled by the valve 44:. This va e is detachably mounted on a valve stem 45. To this end the valve has a central hub portion 46 which bears against a collar 47 on the stem 45 and is held in place by a nut 48. The valve chest 37 has a cap 49, the removal of which gives access to the valve. By removing the nut 48, the valve may be detached from the stem and drawn out from the valve chest.

pipes 33, with common de- The valve stem slides in a tubular guide member 50 detachably supported by a housin 51. The guide member 50 has an an nu ar shoulder 52 which seats on the rim of a sleeve 53 carried by the housing 51 and below the sleeve '53 the guide member is threaded to receive a nut 54 which detachably secures it in place. The valve gear is operated. by a cam 55 hereinafter referred to, and to this end the valve gear includes a head 56 sliding in the housing 51 and carrying a pin 57 on which is mounted a cam roller 58. The roller kept to its duty by a spring 59 hearing, respectively, against the head 56 and an abutment late -80 removably secured to the housing 51. The valve stem detachably connected to the head 56. As shown, the end of the stem is threaded into the head and is held in place by a lock nut 31. The housing 51 is provided with caps 62 which may be removed to give access to the nuts 5st and 61 andkthe plate 60. It the nut bl is removed valve and valve stem may be withdrawn. by removal of nut 54 and the abutment plate 60 the entire valve gear down to the head 56 is bodily removable, and the head 56 and spring 59 may be withdrawn through the opening covered by cap 62 by removing pin 57 or may be withdrawn downward with the pin and roller by removing cam 55 and its shaft.

The valve construction above described is not only extremely simple and convenient, but at the same time all the moving parts of the valve gear are inclosed by the valve chest or housing.

The cams 55, which actuate the valve gear have a differential circumference, and are designed to give the valves a varying point of cut off depending on their longitudinal position with respect to their rollers. These cams, which are duplicates, are rotated by a cam shaft 64 driven by a worm gear indicated at 65, operated as usual from the engine shaft.

The invention includes provisionfor the regulation of the speed of the engine dependent on both the engine speed and the pressure of the fluid being pumped. This is accomplished by causing longitudinal movement of the cam shaft to vary the point of cut off. In the present embodiment, the

camshaft 64 is made in two parts coupled together by a sleeve 63 fixed to the driving partof the cam shaft and in which sleeve the part of the cam shaft carrying the cam is splined so as to be capable of longitudinal movement while rotating with the sleeve and driving part of the shaft. Mounted on the cam shaft is a centrifugal ball governor 67 having one end of its links pivoted to a sleeve 10 splined on the shaft and free to move longitudinally thereon, and the other end pivoted to a sleeve 11 which is splinedon the shaft to rotate therewith but fixed against longitudinal movement. This governor moves the cam carrying portion of the cam shaft 64 to the right in the figures as the governor weights are thrown out, by engagement of sleeve 10 with collar 12 fixed on the shaft, and permits the return of the shaft by spring 80 on the movement of the sleeve 10 to the left as the weights move inward, thereby moving the cams to vary the point of cut-off, this variation depending upon the engine'speed.

The cam shaft 64is shifted also in accordance with the pump pressure, the speed under pressure is, admitted into this channel so as to subject the sleeve to a pressure depending on the pump pressure. To this end, opening into channel 7 5 is a pipe 76 leading to a pressure regulator 77 connected in turn by a pipe 78 with the delivery pipe or air chamber of the pump. This pressure regulator contains a fluid, the pressure of which is dependent on the pump pressure. The regulator pressure being transmitted to channel 7 5, its force is exerted against the shoulder 74 of the sleeve thereby tending to move the sleeve longitudinally to the right in the figures. This movement shifts the cam shaft and the cams. An opposing pressure is derived from a coil spring 80 hearing against a head 81 formed on the sleeve, and against a collar 82. For adjustment of the spring pressure, the collar is threaded onto a sleeve 83 which is rotated by a hand wheel 84. To prevent collar 82 from rotating with sleeve 83, the collar carries a pin 85 moving in a slot in cylinder 70. Sleeve 69 preferably carries a pointer 88 moving over a scale to show the point of'cut-off. For manual adjustment of the cam shaft and cams, a hand wheel 86 is threaded onto a stem 87 secured to head 81 of the sleeve 69. This ressure regulator for controlling the cut of? by the pump pressure is preferably used, but it will be understoodthat the construction may be used without it, in which case the port 75 will connect only with the dash pct 98 with adjustable needle valve 99 which is preferably used in all cases to check vibration.

It will be seen that the combined centrifugal governor and pressure governor operates as follows:

The pumping pressure controls the point of out off by acting on the piston or shoulder 74 for earlier out off as the pressure rises, spring 80 acting to return the piston and cam shaft 64 for later cut-off as the pressure falls, this action being independent of the centrifugal governor, the cam shaft 64 and collar 12 moving freely through the sleeves 10, 11. The pressure will thus control the speed so as-to maintain under normal conditions a substantially uniform pressure and speed independentlyof the centrifugal governor. If the speed rises too high, the centrifugal governor weights will fly out sufficiently so that the sleeve 10 engages the collar 12 and moves the cam shaft 64 to the right independently of the pressure governor to advance the cut-off and reduce the speed, this centrifugal governor thus acting as a safety device to assure the proper speed control. If the pressure governor be not used, as described above, the control of the cut-off will be wholly by the centrifugal governor acting to move the cam shaft 64 against spring 80 and to control. the return of the cam shaft by the spring.

Means is provided for stopping the engine reac es when the cam shaft has been shifted to a determined point. -This is done by locking the shaft against any relative movement,

thereby cutting ofi' the steam supply. In the resent embodiment, in the wall of cylinder $0 is a spring pressed latch 90 having 'a slanting face toward the sleeve 69. In this sleeve, near the end, is an annular groove 91. Latch and roove are so positioned that when the cam shaft has been shifted by the centrifugal governor or pressure governor to such an extent that the cams are no longer operating the valve gear, the latch slides into the groove and the sleeve is locked to prevent return of the cam shaft. As a result, the steam supply is shut ofl from the engine until the latch 90 is manually released.

As shown, means are provided for breaking the condenser vacuum through pipe 92 leading to the condenser. Connected there with is an air pipe 93 normally closed by a valve designated at 94. This valve is operated by a rod 95 having a collar 96 against Which bears a trigger 97. The end of this trigger is located in the path of the sleeve 69. When sleeve 69 has reached a given position, its end strikes the trigger 97 and thus opens the valve 94 and admits air to the condenser.

The operation of the combined engine and pump Wlll be clear from the foregoing without further description.

What is claimed:

1. In a combined engine and pump, a valve gear for controlling the steam supply of the engine, a centrifugal speed governor and valve control mechanism for varying the point of cut off, a connection between the centrifugal speed governor and valve control mechanism permitting the valve control mechanism to move independently of the speed governor, and a pressure governor controlled by the pressure of the fluid being pumped, connected to the valve control mechanism to vary the point of cut 0d independently of the speed governor, and operable without lost motion regardless of the position of the valve control mechanism under movement by the speed governor.

2. In a combined engine and pump, a cam shaft rotated by the engine, a cam mounted on said shaft for operating the engine valve gear, and means for adjusting said cam to regulate the speedof the engine in accordance with the speed of said shaft and for adjusting said cam by the pressure of the fluid being pumped and independently of the speed.

3. In a combined engine and pump, valve gear for controlling the steam supply of the engine, a cam shaft rotated by the engine and capable of longitudinal movement, a differential cam, mounted on said shaft, for operating said valve gear, and means for longitudinally moving said cam shaft in eecordance with the speed of the engine and independently of the speed in accordance with the pressure of the fluid being pumped.

4:. In a combined engine and pump, valve gear for controlling the steam supply of the engine, a cam shaft rotated by the engine and capable of longitudinal movement, a differential cam mounted on said shaft for operating said valve gear, a centrifugal governor associated with said shaft to longitudinally move the same in accordance with its speed, and pressure operated means dependent on the pressure of the fluid being pumped for longitudinally moving said shaft independently of the centrifugal gov-- ernor.

5. In a combined engine and pump, valve gear for controlling the steam supply of the engine, a cam shaft rotated by the engine and capable of longitudinal movement, a differential cam mounted on said'shaft for operating said. valve gear, a centrifugal governor for longitudinally moving said cam shaft in accordance with the speed, and means for longitudinally moving said cam shaft in accordance with the pressure of the fluid being pumped independently of the centrifugal governor.

6. In a combined engine and pump, valve gear for controlling the steam supply of the engine, a cam. shaft rotated by the engine and capable of longitudinal movement, a differential cam mounted on said" shaft for operating said valve gear, a centrifugal governor on said shaft mounted to permit the shaft to move longitudinally independently of the centrifugal governor, a cylinder, a sleeve therein connected with said cam shaft for longitudinal movement therewith, said sleeve having a pressure receiving portion, means for subjecting said sleeve to pressure dependent on the pressure of the fluid being'pumped, and a spring for pressing said sleeve in the opposite direction.

7. In a combined engine and pump, valve gear for controlling the steam supply of the engine, a cam shaft rotated by the engine and capable of longitudinal movement, a differential cam mounted on said shaft for operating said vaive gear, means for longitudinally moving said cam shaft in accordance with the pressure of the fluid being pumped, and means for locking said shaft to stop the engine when it has reached a determined position.

8. In a combined engine and pump, valve gear for controlling the steam supply of the engine, a cam shaft rotated by the engine and capable of longitudinal movement, a difi'erential cam mounted on said shaft for operating said valve gear, a centrifugal governor associated with said shaft to longitudinally move the same in accordance with its speed, and means for locking said shaft e551. milk) to stop the engine when it has reached a determined position.

9. In a combined engine and pump valve gear for controlling tne steam supply oi the engine, a cam shaft rotated by the engine and capable of longitudinal movement, a differential cam. mounted on said shaft for operating said valve gear, a centrifugal governor associated With said shaft to longitudinally move the same in one direction in accordance with its speed, a spring for returning the shaft, a pressure governor con trolled by the pressure of the fluid being pumped and connected for longitudinally moving said shaft independently of the centrifugal speed governor, and a fluid dash-pot for checking the movements of the shaft.

10.12;. a combined engine and pump, valve gear "for controlling the steam supply of the engine, a cam shaft rotated by the engine and capable of longitudinal. move- 11151125 adiiierenrtial cam mounted on said shaft for operating said valve gear, a centrifugal governor on said shaft having its shaft-moving member free to slide on the shaft and a fixed member on the shaft for moving the latter, whereby the shaft may be moved longitudinally for earlier cutofi independently of the centrifugal governor or by the centrifugal governor on engagement With said fixed member on the shift means for longitudinally moving said cam shaft independently of the movement of the centrifugal governor and in accordance with the pressure of the fluid being pumped, and a spring for returning the cam shaft, whereby the steam supply is con trolled independently by the centrifugal governor and the pressure governor.

In testimony whereof l have hereunto my hand.

DAVE) A. DECRQW. 

